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Medical Dictionary

substance

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noun sub·stance \ˈsəb-stən(t)s\

Medical Definition of substance

  1. 1:  physical material from which something is made or which has discrete existence <the substance of nerve tissue>

  2. 2:  matter of particular or definite chemical constitution

  3. 3:  something (as alcohol, methamphetamine, or marijuana) deemed harmful and usually subject to legal restriction <heroin is a controlled substance> <substance abuse>





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